Two‐Colored Organic Photovoltaic Modules Enabled by Laser Annealing

Thermal annealing is a crucial step during the fabrication of organic photovoltaics (OPV). In this work, for the first time, we use a CO ₂ laser to perform contactless and spatially resolved annealing of solar cells and modules based on P3HT:O‐IDTBR—an active material system that shows a color change upon annealing. The effect of laser annealing is thoroughly investigated by different optical, electrical, and morphological characterization techniques and compared to the commonly used hotplate annealing, finding similar results for both annealing techniques. Furthermore, we upscale our developed laser annealing method and apply it to fabricate two‐colored organic photovoltaic modules with 6.0% PCE on 10 cm ² and 5.0% on 201 cm ² . Finally, we demonstrate that CO ₂ laser annealing can also be applied to novel high‐performance material systems such as PM6:Y6‐C12:PC ₆₁ BM.